
First-Aid Kits for Circuit Boards
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7.1.3 Solder Joint Acceptance Criteria
Outline
This document includes figures and tables for solder joint acceptability criteria on a variety of component types.
Minimum Skill Level - Intermediate
Recommended for technicians with skills in basic soldering and component rework, but may be inexperienced in general repair/rework procedures.
| Procedure References |
| 1.0 |
Foreword |
| 7.1.1 |
Soldering Basics |
| IPC-A-610 |
Acceptability of Electronic Assemblies |
| J-STD-001 |
Requirements for Soldered Electrical and Electronic Assemblies |
Figure 1: Dimensional Criteria for Through Hole Components
Table 1: Acceptable Solder Criteria for Through Hole Components
| Feature |
Dim |
Class 1 |
Class 2 |
Class 3 |
| Circular wetting of solder of the lead and plated hole barrel on the component side. |
1 |
Not Specified |
180 deg |
270 deg |
| Plated hole fill. |
2 |
Not Specified |
75% |
75% |
| Circular fillet and wetting of solder of the lead and plated hole barrel on the solder side. |
1 |
270 deg |
270 deg |
330 deg |
| Percent of the land area covered with solder on component side. |
3 |
0 |
0 |
0 |
| Percent of the land area covered with solder on the solder. |
4 |
75% |
75% |
75% |
Figure 2: Dimensional Criteria for Chip Components
Table 2: Acceptable Solder Criteria for Chip Components
| Feature |
Dim |
Class 1 |
Class 2 |
Class 3 |
| Maximum Component Side Overhang |
1 |
Less than 50% of the component termination width or 50% of the pad width whichever is less. |
Less than 50% of the component termination width or 50% of the pad width whichever is less. |
Less than 25% of the component termination width or 25% of the pad width whichever is less. |
| Maximum Component End Overhang |
2 |
Not permitted. |
Not permitted. |
Not permitted. |
| Minimum End Joint Width |
3 |
50% of the component termination width or 50% of the pad width whichever is less. |
50% of the component termination width or 50% of the pad width whichever is less. |
75% of the component termination width or 75% of the pad width whichever is less. |
| Minimum Side Joint Length |
4 |
Evidence of proper wetting. |
Evidence of proper wetting. |
Evidence of proper wetting. |
| Maximum Fillet Height |
5 |
Solder may overhang the pad but must not touch the non-soldered portion of the component package body. |
Solder may overhang the pad but must not touch the non-soldered portion of the component package body. |
Solder may overhang the pad but must not touch the non-soldered portion of the component package body. |
| Minimum Fillet Height |
6 |
Evidence of proper wetting. |
Evidence of proper wetting. |
Equal to the solder thickness plus 25%, or equal to the solder thickness plus 0.50 mm (.020"), whichever is less. |
| Minimum Solder Thickness |
7 |
Evidence of proper wetting. |
Evidence of proper wetting. |
Evidence of proper wetting. |
| Minimum End Overlap |
8 |
Evidence of any overlap is required. |
Evidence of any overlap is required. |
Evidence of any overlap is required. |
Figure 3: Dimensional Criteria for J Lead Components
Table 3: Acceptable Solder Criteria for J Lead Components
| Feature |
Dim |
Class 1 |
Class 2 |
Class 3 |
| Maximum Lead Side Overhang |
1 |
No more than 50% of the lead width. |
No more than 50% of the lead width. |
No more than 25% of the lead width. |
| Maximum Lead Toe Overhang |
2 |
Not specified. |
Not specified. |
Not specified. |
| Minimum Lead End Joint Width |
3 |
50% of the lead width. |
50% of the lead width. |
75% of the lead width. |
| Minimum Side Joint Length |
4 |
Evidence of proper wetting. |
Side joint length must exceed 150% of the lead width. |
Side joint length must exceed 150% of the lead width. |
| Maximum Fillet Height |
5 |
No maximum, but solder must not touch the component package body. |
No maximum, but solder must not touch the component package body. |
No maximum, but solder must not touch the component package body. |
| Mininimum Heel Fillet Height |
6 |
Evidence of proper wetting. |
Equal to the solder thickness plus 50% of lead thickness. |
Equal to the solder thickness plus 100% of lead thickness. |
| Mininimum Solder Thickness |
7 |
Evidence of proper wetting. |
Evidence of proper wetting. |
Evidence of proper wetting. |
Figure 4: Dimensional Criteria for Gull Wing Components
Table 4: Acceptable Solder Criteria for Gull Wing Components
| Feature |
Dim |
Class 1 |
Class 2 |
Class 3 |
Maximum Lead
Side Overhang |
1 |
No more than 50% of the lead width or 0.50 mm (.020") whichever is less. |
No more than 50% of the lead width or 0.50 mm (.020") whichever is less. |
No more than 25% of the lead width or 0.50 mm (.020") whichever is less. |
Maximum Toe
End Overhang |
2 |
Toe overhang is acceptable as long as it does not violate electrical clearance. |
Toe overhang is acceptable as long as it does not violate electrical clearance. |
Toe overhang is acceptable as long as it does not violate electrical clearance. |
| Minimum End Joint Width |
3 |
50% of the lead width. |
50% of the lead width. |
75% of the lead width. |
| Minimum Side Joint Length |
4 |
Equal to the lead width or 0.50 mm (.020") whichever is less. |
Equal to the lead width or 0.50 mm (.020") whichever is less. |
Equal to the lead width or 0.50 mm (.020") whichever is less. |
| Maximum Heel Fillet Height |
5 |
No maximum, but solder must not touch the component package body. |
No maximum, but solder must not touch the component package body. |
No maximum, but solder must not touch the component package body. |
| Minimum Heel Fillet Height |
6 |
Evidence of proper wetting. |
Equal to the solder thickness plus 50% of lead thickness. |
Equal to the solder thickness plus 100% of lead thickness. |
| Minimum Heel Fillet Thickness |
7 |
Evidence of proper wetting. |
Evidence of proper wetting. |
Evidence of proper wetting. |
This procedure is for reference only. Refer to the Procedure References listed above, or contact Circuit Technology Center for appropriate industry approved references.
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Phone: 978-373-1600 - Fax: 978-372-5700
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